In March 1976, he pressed the issue of a member of the House of Commons catering staff who had been found to be a supporter of the Provisional Irish Republican Army, calling for stricter vetting. A strong supporter of Margaret Thatcher, Brotherton urged Edward Heath not to make public criticisms of her. In 1977, he successfully moved a private member's motion that declared the House would not welcome Idi Amin's presence at the Commonwealth Heads of Government Conference. He was also a supporter of Ian Smith in Rhodesia, and urged the government not to make a deal with the "terrorists", including Robert Mugabe. Under the Thatcher government Brotherton supported the call for a boycott of the 1980 Moscow Olympics, and voted against a rise in petrol duty which was proposed by Geoffrey Howe in the 1981 budget. He was placed on the Select Committee on the Contempt of Court Bill in 1981 as one of the few non-lawyers; he supported an amendment to allow unrestricted tape-recording of court proceedings, against government advice. He also opposed the 1981 Defence Review, with its proposed reductions in the Royal Navy. In March 1982, when the Adam Smith Institute rated MPs according to their tendency to vote for individual freedom, Brotherton and his Parliamentary neighbour Michael Brown topped the list. In December 1982, Brotherton (a strong opponent of wasteful spending) was embarrassed when he missed a rail connection and then asked three police cars to drive him from Newark-on-Trent to a charity event in Grimsby. The local Labour-controlled police authority questioned why it was so urgent for him to get there when he was not expected to attend (his wife was the guest of honour), and asked him to reimburse the cost. He was also twice convicted of driving offences in the early 1980s. 1983 election At the 1983 general election, boundary changes merged most of his seat with Brigg and Scunthorpe to form a new Brigg and Cleethorpes; this pitched Brotherton into a contest with Michael Brown for the nomination, which Brown won in March 1983. The remainder of the area became part of the East Lindsey constituency, which adopted sitting Horncastle MP Sir Peter Tapsell. Brotherton then tried to find another constituency, but was unsuccessful. Later career Brotherton kept up contacts in his old constituency and continued living in Lincolnshire. In 1986, he formed Michael Brotherton Associates, a company of Parliamentary consultants.